CONYERS -- Local and state authorities are working to determine why the victim of a fatal fire did not respond to smoke alarms in her home.

Dana Smith, 40, of 1086 West Adrian Circle died as a result of a fire that destroyed her home Thursday afternoon.

Rockdale Fire Department Chief Dan Morgan said firefighters responded to the blaze within 4 minutes of receiving the 3:30 p.m. call, but the fire, which apparently started in the kitchen, had been burning for quite some time. The exact cause of the fire remains under investigation.

"It was called in by a neighbor who had gone over there to do a little neighborly yard work, weedeating around the mailbox," Morgan said.

The neighbor saw smoke coming from the roofline and called 911, he said.

When firefighters arrived, Morgan said they found the heat and smoke inside the house had reached an intense level.

"The smoke was all the way to the floor, which is indicative of a fire that has had a lot of lead time on us," Morgan said.

He also said every room in the house from floor to ceiling had been charred, another indication of a fire that generated a lot of heat in a constrained environment.

Firefighters had been alerted by the neighbor of the possibility that Smith was inside. Morgan said they found her partially lying on a bed in the front bedroom."We're still trying to figure out why she didn't respond to the smoke detectors or what led to her being unable to self-extricate," he said. "I don't know why; we are still looking into that."Smith's husband was at work at the time the fire broke out. Morgan said he arrived on the scene with some other family members.

A family dog inside the house also died in the fire.

Morgan said today's construction methods result in a tighter house that can increase smoke and heat build up inside during a fire. In addition to the dangers of smoke inhalation, Morgan said household contents can release harmful fumes when burned.

"The stuff we buy ... that is made of things other than wood and cloth, burn with different off-gases that, in some cases, can be a quicker poison rather than just campfire smoke," he said.